| ( | x | × | 70 | × | 2 5 | + | x | × | 30 | × | 3 5 | + | 400 | × | 3 2 | × | 2 5 | × | 80 | × | 1 2 | + | 400 | ) | × | 9 10 | = | 30286 |
| 方程左边 = | x | × | 70 | × | 2 5 | × | 9 10 | + | x | × | 30 | × | 3 5 | × | 9 10 | + | 400 | × | 3 2 | × | 2 5 | × | 80 |
| = | x | × | 126 5 | + | x | × | 81 5 | + | 8640 | + | 6480 |
| = | 207 5 | x | + | 15120 |
207 5 | x | + | 15120 | = | 30286 |
207 5 | x | = | 30286 | − | 15120 |
207 5 | x | = | 15166 |
| x | = | 15166 | ÷ | 207 5 |
| = | 15166 | × | 5 207 |
| x | = | 75830 207 |
| x | = | 366.328502 |